The present invention relates to an apparatus and associated method for housing a circuit and, more particularly, to an apparatus and associated method for shielding a circuit from electromagnetic interference.
Electronic circuitry is used in a wide variety of applications, such as controlling the deployment of air bags in a occupant protection system. An electronic circuit is often formed or mounted upon a circuit board. The operation of electronic circuitry can be adversely affected by electromagnetic interference. Shielding electronic circuitry from electromagnetic interference can, therefore, improve the operation of the circuit.
The amount of electromagnetic interference to which electronic components are exposed can be limited by locating the components in a protective housing which shields the components from the interference. U.S. Pat. No. 5,872,332 discloses a molded housing with EMI shield. A metal shield is stamped from sheet metal into a box shape. The stamped metal box shields the circuit from electromagnetic interference. The metal box is then insert molded into a plastic housing. The plastic housing is a polymer material, such as polyethylene terephthalate. A circuit board containing necessary components is then placed within and secured to the housing.
The present invention is directed to a housing and associated method for shielding a circuit from electromagnetic interference, in which a molded portion of the housing is received within an aperture for securing parts of the housing together.
In accordance with one exemplary embodiment of the invention, a housing for shielding a circuit from electromagnetic interference comprises a shielding component having at least one aperture. A plastic material is molded over the shielding component. A portion of the plastic material is received within the at least one aperture for securing the plastic material to the shielding component.
In accordance with another exemplary embodiment of the invention, a method of making a housing for shielding a circuit from electromagnetic interference includes the steps of providing a shielding component having an aperture; molding a plastic material over the shielding component; and, securing the plastic material to the shielding component by receiving a first portion of the plastic material into the aperture in the shielding component.